Changes with nginx 1.6.3 07 Apr 2015

    *) Feature: now the "tcp_nodelay" directive works with SPDY connections.

    *) Bugfix: in error handling.
       Thanks to Yichun Zhang and Daniil Bondarev.

    *) Bugfix: alerts "header already sent" appeared in logs if the
       "post_action" directive was used; the bug had appeared in 1.5.4.

    *) Bugfix: alerts "sem_post() failed" might appear in logs.

    *) Bugfix: in hash table handling.
       Thanks to Chris West.

    *) Bugfix: in integer overflow handling.
       Thanks to Régis Leroy.